Biological Nightmare
by made.for.life
Summary: The Avengers are exposed to deadly creature living inside them. Things seem hopeless until Bruce brings up an old friend.
1. Chapter 1

"What do you mean infected?" Clint barked.

All the Avengers looked sternly at the man before them.

Nick Fury sighed. "I mean that you were all infected during your last mission. The researchers must have been playing around with something extremely dangerous and you all are contaminated."

"What is it?" Bruce crossed his arms. "Viral? Bacteria? Infectious?" He was fairly skilled at all of the above.

The black man shook his head. "It's biological. That is to say it's living in you and growing."

They all shivered.

"The problem is it's beyond anyone we have a board or are in contact with's range of knowledge. Everything we have tried it adapts to." He studied them. "Even Thor is being harmed internally by this."

Silence fell as everyone regarded the tallest Avenger who frowned looking at one of his hands.

"So what do we do?" Steve asked. He had learned to have faith in modern day America and her people.

"I'm sorry." Nick shook his head. "There isn't a thing we can do here at all. We've been trying and we'll keep trying but we don't have the resources for this."

"What are you saying?" Thor asked crossly.

"You're on your own." Nick walked out.

"Hey!" Tony went to stand but sat back down sweating.

They all looked at one another. What had just happened? Were they going to die? Natasha was the first to stand and they walked out of the room to the plane waiting to take them back to Tony's Malibu house where they were all staying. Once they arrived Bruce walked out last and stood turned skyward as the pilot flew the bird off. He turned back.

"Well this sucks." Tony said sitting at the kitchen. "How is it that I'm always dying from one thing or another?" He tapped his reactor absentmindedly.

"I always thought I would bite the bullet from a bullet." Clint joked without any humor.

Thor looked at them. "Do we have no other choice then? We sit and contemplate our funeral marker?"

"Mine does not go back to Russia." Natasha grimaced.

Steve just sat palely. "Maybe they'll find something?"

Tony looked at the ground. No on even had the heart to speak the hopelessness of their case.

Bruce came in. "Well arlighty then." He clapped his hands together. "How much time would it take a helicopter to get to the Amazon Rainforest, Tony?"

"One of mine?" He sat upright abruptly. "An hour at full speed."

"You have something rage brother?" Thor perked up hopefully.

Bruce looked around. "I have a hope, one hope, one try."

"Well let's go!" Steve jumped up.

"Jarvis call the Spyhopper!" Tony ran up to his room to change out of his suit.

"We'll need to make a quick stop." Bruce shouted over the noise of the blades as they boarded the copter.

"Where?" Tony yelled.

"Tony we have a problem!" Steve looked out frantically, interrupting them. "The pilot's gone!"

Tony dragged a hand down his face and shoved Thor in before him. "The chopper flies itself Spangles." He turned back to Bruce as Clint climbed into the body with him and Natasha sat next to him. "Where?" He pulled out his tablet to program in Bruce's stop while Steve muscled the door shut.

The helicopter landed a second time after the doctor's detour. There was barely enough space to put the bird down where they landed near a tiny village. None of the people dared approach them at all. They entered the jungle to start their tramp through it.

"I still do not comprehend why you have a bag of food Doctor Banner." Thor said.

"Yeah, why did we stop at McDonald's?" Steve looked at him.

"Well the girl we are going to see is a lot like Tony." Bruce panted lightly. The thick scrub made it very hard to walk. "She forgets to eat but she doesn't really have anyone else to feed her. I always bring food. MickyD's is one of her favorites."

"Why's she live out here?" Tony was breathing more heavily.

"Let's leave it as she had a very bad experience with humanity." He looked down sadly. "Then she has a bit of a strange appearance now so she won't even try coming back."

"Strange how?" Natasha asked.

Bruce contemplated that. "I think you need to see it to believe it."

He stopped suddenly. They were in a shallow dry river bed. A rock cliff rose up one side. The curly haired man climbed awkwardly with one arm up the embankment. He pushed aside a few clumps of foliage and disappeared through them. The rest of the Avengers followed. There was a fairly good sized space with a wooden table and chairs at its center. The light only made it part of the way across the room and the opposite side was shrouded in deep shadows. Figures stood, various other wooden furniture littered with papers stood around some unseen.

"Bruce?" Tony questioned.

The man shushed him. He set down the McDonald's bag and pulled out the cheeseburgers and fries. He set the out on the table then stood back quietly.

"Sasha." He hummed gently. "I know you're here. I brought food. These guys here" he nodded back toward the Avengers, "have just as many secrets or more than you do. They won't hurt you either."

There was a slow, languid motion from the shadows of the room. The stature of a person swayed forward. She was incredibly thin and sallow skinned. She had a shredded and colorless from multiple washes shirt on. Through holes they could see bandaging around her chest and ribs. A faded pair of jeans covered part of her legs. The seams at the bottom were gone, exposing a pair of heavy, ratty leather boots. To top it all off a grey-brown lab coat was thrown over her shoulders, covering her arms.

"Hi Sash. We need some help." Bruce sat down at the table with her. "We got into a bit of trouble."

He explained the mission that went horribly wrong, the bio hazardous chemicals and disease they had been exposed to, and their current status of kicking the bucket list. She stared at him quietly. The girl chewed up her last fry.

"Can you give us a hand?"

"Of course." She nearly whispered.

The Avengers finally got a good look at her face. Her eyes had a hawk like appearance. She motioned them after her into the shadows. Tony pulled out his cellphone and held it up for a flashlight. A straight shot tunnel lead them away from the tiny room. Thor had to duck at some points as the tube wound on. The floor was worn from many a travel of feet.

"Careful." Natasha caught Steve's arm before he fell.

The soldier smiled. "Thanks."

Finally, the tunnel abruptly cut off into a much larger room. It glowed with bright light bouncing off the stark white rock of its ceiling and floors. There were tables with equipment sitting around all neatly encased with dust covers.

Tony examined all the different microscopes and incubators. "How do you get electricity out here?"

"She makes her own." Bruce answered for her.

The female, Sasha, hurried around taking the cover off of a certain flat piece of equipment. She set a beaker with boiling water on it. She shuffled open other drawers pulling out tubes and needles.

"She gonna need blood samples too?" Tony groaned.

Steve twitched. He had had a difficult enough time with all the blood drawn before. Natasha sympathized with him.

"Sorry." She murmured to them.

Bruce walked over to the sturdy but raggedy chair she had dragged up. He sat down and rolled up his sleeve farther. Sasha had a long bit of rubber in her mouth and a bit of paper. The needles and tubes that had been dunked in the boiling beaker over the burner lay on her tray. She tied the rubber around the doctor's upper arm and expertly found his vein. She got it in one go and drew his blood into a vial. As soon as it filled the needle vanished and she pulled the band aide out of its paper with one hand.

Everyone else's samples went just as quickly. Thor, back at Shield had had to sit still through multiple stabs because the doctors couldn't find his blood vessels. One had even rolled the needle around in his arm. Sasha found it in one poke and the large Asguardian sighed in relief.

"Can she work with so little?" Thor asked Bruce.

Bruce nodded. "She is the best."

The female hurried around pulling dust covers off microscopes and slide holders. She put a drop of blood on the slide and marked it. Then she dropped others on separate slides and looked up.

"What are your names?" Sasha asked quietly.

"I'm Steve Rogers." The super soldier held up his hand.

Thor smiled. "I am called Thor Odinson in your tongue."

"Clint Barton." The assassin called from where he was studying the room.

"Tony Stark." The inventor crowed proudly.

"Natasha Romanoff." The red haired assassin put in finishing the list.

After each name the girl scrawled on the slides. She put them under the microscope one at a time. Her hand seemed to work independently to scrawl on the paper next to her. She paused every once in a while to rub her eyes. The Avengers watched her with interest. Suddenly she took off running down another tunnel near the back of the room.

"Come on." Bruce waved.

They sprinted down the straight shot tunnel. Thankfully there were no other routes because they could not catch up to her at all. The tunnel again cut off abruptly to a huge room that was perfectly circular. The walls were one huge circular shelving system. In the middle of the room and dirty lab coat lay slumped on the floor.

"She ditched us." Clint said incredulously.

"Never." Bruce said. He pointed upward.

Tony gasped. The rest were stunned to silence. The girl was high in the air near the top shelves with a mail bag over her shoulder. Funny thing about her shoulders is four massive, sheet white wings spread from them. Twin larger wings beat firmly holding her up in the air as she searched the shelf. Smaller wings were lower but still beneath the primary wings fluttered quick circles. They stabilized her single spot in the air. She pulled several jars from the shelf then went up higher.

She scowled. "Damien, move it!"

There was a rumble from the shelf and a silver and cobalt form dropped from the shelf. It opened its arms that were lined with feathers and started in slow circles.

"That's a dinosaur!" Steve yelped.

The raptor like feathered thing spotted them and roared. It dropped straight to the floor. Sasha made as if to come down.

"You're fine." Bruce waved her off. He approached the shoulder high blue silver dinosaur. "Hey Damien. Do you remember me?"

The thing with a scaly muzzle and bright grey eyes snapped at him then sniffed. It tilted its head and hummed.

"That's a boy." Bruce scratched up the thing's chin and it garbled.

Sasha crawled into the far reaches of one of her shelves.

"Wait is that actually a prehistoric creature?" Tony stood by his science buddy's side.

Bruce nodded as Tony reached forward to pet Damien. "It's one of her crowning achievements she says. I don't know why the wings on her back aren't the best but Damien is a perfectly healthy Unenlagia."

"Pretty too." Natasha put in standing an objective two feet from Damien's flank. There was a flurry of flutters above them as Sasha spiraled gracefully to the ground. All four of her wings folded neatly to her back and she slide the coat back on.

"You can leave it off if you want." Natasha shrugged.

"Lab safety regulations." She smiled for the first time. "Long sleeves, close toed shoes, and"

"Eye protection." Tony and Bruce said with her.

She nodded and sprinted back down the hallway she had come from. The feathered dinosaur sprinted with her. The Avengers felt like ducklings running again after the female.

"Is this the little different part or are we in for another shock?" Natasha asked as they returned to the laboratory.

Bruce chuckled. "That's all I know of but there's always something new around here."

"Fantastic." She muttered.

Thor was watching her carefully. "Where are her care-keepers? Has she no mother or father?"

Bruce shook his head a bit sadly. Damien came wandering over bored with Sasha's research. Bruce scratched him absentmindedly.

"I've never been in a very good position to help her; every time I've come here I've been dying or absolutely desperate." The doctor watched the girl flip the slides around. "She's the one that suggested the balance that I keep now. The idea that the big guy and I were twin entities sharing a body instead of a power push between us was her thought process."

"Um. Bruce?" Tony backed up putting up an arm. "Help?"

The dinosaur was sniffing at him deeply and hungrily.

"Stark. What was the last food you kept in your pocket?"

"Uh?" Tony stepped back thinking fast. "Beef Jerky."

The doctor sighed. "Thought so. He loves the stuff."

There was a sound and something flew through the air.

Clint caught it midflight. "Hey looky here." He gave the bag a shake. He was suddenly knocked off his feet and lay under a prehistoric body. "Ok! Ok! Here." He fed the thing little bits.

The girl gave a slight whistle suddenly. Damien strode over in the particular swaying way that dinosaurs do. He leaned down and sat still and she took another needle and withdrew a few vials of blood from him.

"What's she doing?" Steve asked.

Bruce nodded to the raptor. "Damien is naturally and artificially immune to all diseases and pests on earth."

"So Sasha's going to use his natural antibodies to help us?" Tony figured.

"Hopefully." Sasha said quietly.

She combined the blood samples slowly. The first three went by quickly without a second glance to them. The fourth she studied carefully for a long time but set it away as well. The fifth passed as well. The sixth she frowned and dropped the slide soon after picking it up. It sizzled and hissed, boiling under the slide cover. Sasha turned suddenly reassessing them.

"What's wrong?" Tony asked.

Bruce looked at the ground. "It's mine?"

Sasha shook her head. She studied the form of the largest Avenger. "Asguardian aren't you?"

"I am." Thor answered a bit shocked.

She scowled and ran back off down the tunnel and came back seconds later with a different chemical. She continued working and the Avengers eventually slumped to the floor, entertaining themselves in their own ways. At long last Sasha pushed back from her table and gave them a half smile holding out a hand with instead of needles there were compressed pills.

"That's it?" Steve asked having expected like an operation.

"No needles?" Tony said suspiciously.

"That's it." She said tiredly. "You need strength not speed."

She passed the regular pills to everyone except Thor. His was smaller and an off color.

"All fixed." She said simply recovering her equipment.

"Thank you so much." Steve said sincerely.

Tony shrugged. "Is there anything we can do for you?"

She kind of shrank back at the offer. Bruce recognized it was time for them to leave.

"Sasha." He put a hand on her shoulder. She raised her eyes from the floor. "We honestly can't thank you enough. Things have changed out in the world. We could protect you. People would welcome you to the world for the most part."

She shivered and her eyes twitched fearfully. Bruce nodded and the rest of the Avengers said their goodbyes as they followed the doctor out.


	2. Chapter 2

"She's a good kid." Steve said.

"Such a youngling would be in Odin's service in my home." Thor crossed his arms.

"I'm having a hard time picturing you leave her there all these years." Natasha remarked.

Bruce spread his hand in helpless frustration. "I wasn't exactly in the position to adopt or anything. I'm rarely in any mindset to bring her food when she is my last resort."

"You didn't **use** to be in a place to help her." Tony emphasized. "Now on the other hand, you have the superhuman Avengers support team and Stark Industries may have just taken an interest in a new asset."

Bruce looked at him seriously. "Stark, you can't joke about this. Sasha is very close to me."

"I swear." The inventor crossed his heart. "We could go all out and completely recreate the little set up she had there. Temperature, climate, space, and all."

"She'll never move her stuff." Bruce said.

There was silence.

Steve spoke up. "What if we just moved it all for her? Like a surprise."

Tony stared at him. "Spangles my boy that is brilliant. Ok. Leave this all to Papa Stark!"

A month later they were headed back toward the cave. Thor went first, he was stage one. The Thunder Demigod had located one of the very few Sleipnir that had come to earth. It was something Sasha wouldn't be able to resist visiting.

"I will meet with all you comrades later!" The blonde waved. Minutes later two figures took off into the sky. One flapping wings and the other pulling in thunderheads

"Ok." Bruce spoke into the radio he was holding.

Three huge Black Wing helicopters, which Tony had "modified" just for this, flew in quickly to land at the new jump site. There was a group of people in each one.

"Tony this is just strange." The inventor's friend, Rhodey hopped down.

Tony snorted. "This is charity work and we're just carrying boxes."

"I think it's really kind of you." Pepper gave him an approving glance.

"So where is this place?" One of the other guys asked.

"In the woods a bit." Steve said. "Maybe if we made an assembly line or"

"I think it's safer just to take things." Bruce said. "Some of her materials are a bit volatile."

"Volatile?" Natasha mimed.

"Just a few chemicals." Bruce shrugged. "I'll be careful with those."

"Oh. He'll be careful with them but what about the rest of us?" Clint complained cheerfully.

It wasn't as bad of a task as anyone thought it would be. Damien was coaxed onto a copter with copious beef jerky and shipped on ahead to the house first.

"Very careful with this one." Bruce gingerly handed Clint a glass jar.

The archer took it carefully. After one drop, Bruce had started handing breakable things solely to Natasha and Clint.

"We got everything out of the front cavern and the lab." Tony marched in with Pepper.

"Side areas are clear." Natasha came in with Clint.

"Great." Bruce had smiled more today than anyone had seen in all their time as a team. "Just a few more things up here." He called from the top shelf. He tucked them into his bag and started climbing down.

"Hey do you think she wants her generator thing?" Tony asked looking at the last big piece of equipment.

"I would assume yes except that's an incubator so it needs that auxiliary power source we brought."

Natasha took off to go get it.

Steve walked over. "Do you want me to shift it over to get to the plug?"

"Yeah." Bruce waved him on scanning the shelves from all angles for any bits or bobs they had missed.

Steve shoved the box away from the wall. All of a suddenly the machine started to scream mechanically. The screen flashed red and it shrieked like a siren. Bruce scrambled down the ladder. His phone started to vibrate and he answered it quickly.

There was a soft warbling at the other end.

"What?" Bruce yelled.

"I SAID!" Thor roared into his ear. "YOUR FRIEND RAPIDLY LEFT MY COMPANY AND I AM UNABLE TO LOCATE HER! ARE YOU IN NEED OF ASSISTANCE?"

"YES!" Bruce yelled as the alarm cut off. He slapped the phone shut.

"It didn't like being disconnected." Steve panted giving the extra power source a slap.

"Damn right." Tony scowled at the misbehaving machine. "My babies are better mannered."

"Sasha's coming." Bruce stated.

"What? When?" Tony spun.

"Listen." Natasha hissed.

Another hiss took the place of hers, feathers skimming rock walls. There was a pause. Bruce panicked in his mind. She is going to have a big shock. The hissing skim started again, faster and faster. Bruce looked at his hands. She probably thinks its robbers. The form shot into the circular room they were occupying. Pepper, Rhodey, and the other newbies gasped. Bruce gasped but from the sheer emotion in his younger version's eyes. Confusion. Realization. Hurt and more hurt. Betrayal and disgust. The winged female shook and beat her wings to escape.

"Sasha! Wait!" Bruce shouted. "It's not what you think."

She hesitated half turned to leave, half turned to stay.

"We want you to come with us! I want you too. We moved everything to a new place, closer. Everything is fine except one bottle of formaldehyde. Please." Bruce held out on hand pleadingly. "I want to take care of you."

She beat her wings uncertainly. Looking at his hand. Finally she reached down and took it. He pulled her slowly to his chest the hugged the younger girl tightly to him.


	3. Chapter 3

3 Months Later

"I'm so sorry." Bruce said kneeling next to his friend on the floor.

The scientist put a hand on the slowing heaving side of their companion.

"I guess messing with genes changes lifespan a bit." He said sadly.

The feathers stirred slowly under the gentle hand. The naturalness of death was rather shocking to two such unnatural beings like themselves. The hand soothed over the soft top of the lovely winged creature's head. Their breathing slowed gradual and the scientist sighed heavily pushing the eyelids closed.

"I'm so sorry." Bruce repeated in a whisper.

The Avengers in the background sniffed. Even Natasha had grown fairly attached to their new addition.

"Are you going to be ok?" Tony asked.

The kneeling person stood.

"I'll be ok."

She strode across the floor with a purpose. The incubator hummed still as she retrieved a sheet to cover poor Damien.

"I knew he wouldn't live as long as he should. I was working with pre-aged DNA."

She tapped the incubator as she passed it. "She on the other hand will live for years and years."

Everyone smiled through the sadness and they bore the Unenlagia outside to its new permanent home in the ground.

"Thank you Damien." Sasha whispered. "You helped me through so much and the move especially."

She stood and Bruce had to admire the way she had filled out. He felt honest fatherly pride for making the gaunt pale look turn into this healthy constantly smiling teenager female just like any other. Minus the wings of course. She had gained weight and spent hours poking around town with him and Steve and occasionally Tony too.

"Rest in peace large creature." Thor said.

Bruce just smiled. "Thank you Damien."

Oh Brave New World, with such people in it.


End file.
